Published Removal of a basic dye from aqueous solution by adsorption using rice hulls by El-Maghraby A. and El Deeb H.A.
Published Study of polyacrylic acid adsorption on the interface of hydroxyapatite – electrolyte solutions by Hafez I.T., Paraskeva C.A., Klepetsanis P.G. and Koutsoukos P.G.,